A few weeks ago, we celebrated Administrative Professionals Week at our office by chipping in to treat our administrative assistants to a small party. I took photos and I think among the events I've shot, this one has the results I like best. I'd like to post the photos but I don't have model releases for my colleagues. ;) Anyway FWIW here are some tips I learned from this event.
1. Don't automatically abandon bouncing flash as an option even if conditions seem difficult. Here I had dark grey walls and dark wood ceilings but bounce flash was viable and gave me good results.
Related post: Will it Bounce?
2. Don't be afraid of high ISO. Allowing yourself to use a high ISO on some shots give you more flexibility in determining the lighting for the shot. Don't worry too much about noise -- it's easy to use noise reduction software to take away noise, and unless you're enlarging the photo, most people looking at shots on a web album (or in an actual album) won't see the noise (or reduced detail from noise reduction). However, they will notice the lighting - good or bad - even at small viewing sizes.
3. Consider turning off the flash for some shots. Pay attention to conditions where the ambient light looks great without flash.
Related post: Au Naturel
4. For photos of groups, bounce from a spot on the ceiling/wall that is as far as your flash can manage in order to have an even light over all the people in the group shot.
Related post: an Underrated Bounce Flash Technique
5. Having two cameras -- one with a fast standard zoom, and the other with a fast tele zoom -- gives immeasurably better results than just having one camera. However, if you only have one camera I would say it's more useful to have a wide range than to have a wide aperture zoom. Or you could use a standard zoom and compose your shots with the intent to crop.
6. A fast tele zoom like the Sigma 50-150 is useful for getting flattering photos of the attendees (which seems to be the primary way some non-photographers conclude whether you took good photos of the party). With only three or less people in the shot, there's a higher chance of getting everyone in a good pose than in a large group shot.
Related posts: the Sigma 50-150 is TIGHT
7. If you're taking a group portrait with a wide lens, warn everyone to stay away from the edges of the frame or else they may look wider (fatter). Besides being true, it's also a good way to make people bunch up together, which generally looks better for group photos.
8. During editing, if you have several good photos in a series, instead of forcing yourself to choose only one of the photos in the series, consider picking several photos and combining them into a collage.